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Immunity · 5 min read

Vitamin D: the daily essentials

Why D3 + K2 is the modern default — and how much you actually need.

Vitamin D3 (cholecalciferol) is the form that most efficiently raises serum 25(OH)D.

K2 (MK-7) helps direct calcium to bone tissue rather than soft tissue — a sensible pairing.

Most adults benefit from 1000–4000 IU/day depending on baseline status, latitude, and skin tone. Test if you can.